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Autopilot Disabled at Low Temperatures

Discussion in 'Model S: User Interface' started by Duma, Nov 22, 2015.

  1. Duma

    Duma Member

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    #1 Duma, Nov 22, 2015
    Last edited: Nov 23, 2015
    Autopilot Disabled at Low Temperatures?

    I started a trip this morning with a cold soaked car - parked outside overnight, with outside temperature around 25 F. Power and regen were limited as expected. Got on the highway and while TACC was available, but autopilot was not. (Attempting to engage autopilot with double pull on stalk resulted in the error message "Autopilot temporarily unavailable" and no grey steering wheel icon displayed)

    After about 45 minutes, with outside temperature at 28 F and battery warmed enough to show full regen, autopilot became available (icon appeared) and would enable. As I remember the temperature had briefly showed as 28 F a bit earlier while regen was still limited to about 50 kW but then dropped again.

    I can't imagine why autopilot would depend on having full regen, so I expect that temperature is the key variable. Either the temperature needs to be above some threshold for a minimum time or the threshold is between 28 and 29 F the first 28 F was below this threshold.

    That said, it would make some sense to disable autopilot in icy conditions since that is likely beyond the current hardware and software, and temperature is a simple proxy. I am at a loss to explain why the threshold temperature is 28 F rather than freezing (32 F).

    For completeness, all the sensors were free of snow or ice and the road was clear and dry, with 6+ inches of snow past the highway shoulders. Some dirt on the windshield, driving south into the sun at between 10 and 11 AM, so glare could have been a problem for the camera, but this remained the same throughout the observation period and seems secondary. I've read of snow/ice blocking the radar sensor and disabling both TACC and autopilot, but that does not apply in this case.

    Any other similar experiences out there?
     
  2. Andyw2100

    Andyw2100 Well-Known Member

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    Very interesting observation.

    Autopilot not working at temperatures below 28 (or anything close to that) would mean it wouldn't work for us for most of the winter.

    I hope what you encountered was something else. I'll certainly report if we encounter anything similar.
     
  3. green1

    green1 Active Member

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    I've already used it in colder temps than that and full cold soak, Autopilot worked fine. Doubt it was temperature. The fact that TACC was available proves the radar was working, but I bet visibility was a problem for the camera and it just couldn't see the lines well enough.
     
  4. Cyclone

    Cyclone Active Member

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    In another thread someone posted a photo of their camera fogged up because it's heater element wasn't working to warm up that section of the windshield. I can't recall if they lost TACC either. I thought he camera was used by TACC. Just throwing that out there if it plays a role in what Duma is seeing.
     
  5. mahulkp

    mahulkp Member

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    I had the same experience yesterday. When I started with a cold car the camera wasn't working at all and couldn't read the lines on the road (no error messages). It didn't recognize lights from other cars either so the auto high beam wasn't working. After driving for 20 min the lines started to show up an AP was enabled but it seamed to have s more poor reading. The auto beam started working but also with a poor function, missing cars from time to time. I was driving for 3 hours and it was clear to me that the camera wasn't fully functional in the cold. It was -5c outside. I will report to SC and see what they will do.
     
  6. Andyw2100

    Andyw2100 Well-Known Member

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    That definitely sounds like it could be the problem with condensation in front of the camera, as it is the camera that is used for auto high-beam.
     
  7. Duma

    Duma Member

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    I did not notice any fogging of the windshield in front of the camera but may have missed this since I was not explicitly looking for fogging. I will monitor this more closely in the future.

    That said, speed limits where being displayed and changed when passing the sign, which suggests the camera was working. Lane markings were reasonably clear, but glare from the sun may have been a factor.
     
  8. JeffS

    JeffS Member

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    I've used AP with temps below 20. No problems. Regen still limited. Power not limited.
    I park in an unheated attached garage, temps usually bottom out in my garage in the low 30's. So not cold-soaked the same way as a car left outside for a night. But still...the center stack temp showed (if I remember right) 17deg F on the coldest morning.
    No limitations.

    At the very least, this means it's not an outside temp variable. This does not confirm nor counter that there's a variable at play with battery temp.
    However, after 45mins and no regen or power limits, me thinks that's off the table.

    Of all that was written and considered, the one thing that stood out to me was glare. There's no way to empirically ascertain what the camera can see through the sun, since there's no way for the eye to duplicate the lense nor the position in the car. Just my $.02.
     
  9. wk057

    wk057 Senior Tinkerer

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    I used my car today after it had cold soaked all night in the lower 20s. Barely any regen, but autopilot worked fine.

    I'll put my money on obstructed cam view from condensation or something else.
     
  10. Adrian

    Adrian Title(D)

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    Doesn't have to be on the windshield:
    ZPyCN6o.png
     
  11. meltoots

    meltoots Member

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    Anyone have a method to get rid of the fogged up autopilot camera?
    I drove for an hour in 10 degree weather, never cleared. Tried defrosting front windshield, no luck.


     
  12. vdiv

    vdiv Chief Grump

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    Don't know about you all but at these temperatures the human pilot looks disabled too, not very eager to venture outside. :)

    For the fogged up windshield in the camera cavity, maybe slowly put something warm on top to thaw and evaporate the condensation. Don't apply anything hot or anything suddenly as it will crack the windshield. Maybe just park it facing the sun.
     
  13. Cyclone

    Cyclone Active Member

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    I thought I read that the camera housing is supposed to have a defroster for this very reason, but some cameras have had to be replaced because it is non-functional. Have you asked if your service center if it is supposed to be able to clear frost/fogging like this?
     

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